8- The try-with-resources Statement

Jun 18, 2026 04:36 · 2:26 · English · Whisper Turbo · 2 speakers

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Lecture Index

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S… Speaker 1 (8- The try-with-resources Statement)

In this video I'm going to show you a better way to release external resources

0:07

S… Speaker 1 (8- The try-with-resources Statement)

like file handles and database connections.

0:10

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First I'm going to delete this ugly finally block,

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that's better.

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S… Speaker 2 (8- The try-with-resources Statement)

Now,

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S… Speaker 1 (8- The try-with-resources Statement)

in Java we can declare and initialize our external resources as

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part of the try statement.

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S… Speaker 2 (8- The try-with-resources Statement)

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S… Speaker 1 (8- The try-with-resources Statement)

right after the try keyboard and before the left brace,

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S… Speaker 1 (8- The try-with-resources Statement)

we type a pair of parentheses and inside this parentheses

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S… Speaker 1 (8- The try-with-resources Statement)

we create and initialize our external resources.

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S… Speaker 1 (8- The try-with-resources Statement)

So here we can type var reader equals new file

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reader. Now,

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we delete this line over here and this

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S… Speaker 1 (8- The try-with-resources Statement)

variable declaration over here.

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So this is what we call the try with resources

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statement.

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A try statement that has one or more resource.

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S… Speaker 1 (8- The try-with-resources Statement)

With this structure,

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we don't need to explicitly close this resource inside the

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final block.

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S… Speaker 1 (8- The try-with-resources Statement)

The Java compiler will do that for us.

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S… Speaker 1 (8- The try-with-resources Statement)

So when we compile this code,

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S… Speaker 1 (8- The try-with-resources Statement)

the Java compiler will translate this code to what we had in

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S… Speaker 1 (8- The try-with-resources Statement)

the last video.

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S… Speaker 1 (8- The try-with-resources Statement)

It will add a final block and explicitly close the reader

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S… Speaker 1 (8- The try-with-resources Statement)

object.

1:14

S… Speaker 2 (8- The try-with-resources Statement)

Now,

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for this to work,

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S… Speaker 1 (8- The try-with-resources Statement)

this class should implement the auto -closable interface.

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S… Speaker 1 (8- The try-with-resources Statement)

Let me show you.

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S… Speaker 2 (8- The try-with-resources Statement)

So,

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S… Speaker 1 (8- The try-with-resources Statement)

Here's the documentation for the file reader class.

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S… Speaker 1 (8- The try-with-resources Statement)

Look at the interfaces implemented by this class.

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S… Speaker 1 (8- The try-with-resources Statement)

One of them is auto -closable.

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S… Speaker 1 (8- The try-with-resources Statement)

This interface declares a method

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called close.

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S… Speaker 1 (8- The try-with-resources Statement)

So the close method that we have in the file reader actually comes

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from here.

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S… Speaker 1 (8- The try-with-resources Statement)

So the objects that we create over here should implement

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the auto -closable interface.

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S… Speaker 1 (8- The try-with-resources Statement)

Now we can create multiple objects here.

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S… Speaker 1 (8- The try-with-resources Statement)

Let me show you.

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S… Speaker 1 (8- The try-with-resources Statement)

First I'm going to put this on a new line.

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S… Speaker 1 (8- The try-with-resources Statement)

Now we terminate this statement with a semicolon,

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S… Speaker 1 (8- The try-with-resources Statement)

and then we can create another object.

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S… Speaker 1 (8- The try-with-resources Statement)

New file writer,

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some file.

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S… Speaker 1 (8- The try-with-resources Statement)

Now pay attention to how I have formatted this code.

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S… Speaker 1 (8- The try-with-resources Statement)

I'm following the same convention we have in Java.

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S… Speaker 1 (8- The try-with-resources Statement)

So I put the left bracket right after the

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try keyword,

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and the right bracket over here.

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S… Speaker 1 (8- The try-with-resources Statement)

So this is how we can use the try with resources statement.

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S… Speaker 1 (8- The try-with-resources Statement)

Next I'm going to show you how to throw exceptions in Java.

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